Key Giveaway!

Mann Co. Supply Crate KeyNo conditions required, if you want to win, answer me, these riddle three.
Firstly, if not all three riddles are answered correctly, the person with the most correctly solved riddles will win.
If by the end of the giveaway there is more than one person with all 3 correctly answered riddles, or in joint with the most riddles answered correctly I will do a randomizer for the winner of the key.Good luck!

Riddle 1: There is a tower. There is a room at the top of the tower which cannot be seen from the outside or without entering the room. There is 3 light bulbs at the top of the tower and 3 light switches at the bottom. Only entering the room once, how do you tell which light bulb leads to which light switch?Riddle 2: What is something that is yours but other people use it more than you?Riddle 3: What can travel the entire world, in a single corner?

Turn on number 1, leave it. Turn on number 2, leave it for a while and then turn it off. Leave number 3. Number 1 will be the one still on, number 2 the one that is warm to the touch and number 3 the one that isn't on.
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